Losses in turbomachinery stages vary in strength and character from case to case, but all turbomachinery stages include most of the following mechanisms for single phase, single component, flow: surface friction, secondary flow generation, exit mixing, clearance gap flows, leakage, and shock formation for highly compressible flows. These mechanisms are in turn influenced by many design parameters, such as flow rate, inlet pressure and temperature, exit pressure, incidence, and flow turning plus surface curvature, thickness, and conditions of rotation, amongst others. Losses negatively affect turbomachine performance and are generally understood to be a degradation of the flow state, leading to total pressure decay and an increase in entropy for the flow process. Losses can also lead to flow separation and stall and impeller slip, as well as non-uniform flow fields that frequently negatively impact performance of downstream elements. A need remains for improved devices and methods for reducing losses and mitigating the effects of losses.